The overarching goal of the proposed research is to examine associations between family use of public assistance benefits, family contexts, and the development of low-income children and adolescents. Using nationally representative data from the Early Childhood Longitudinal Study-Kindergarten Cohort, this work will address three specific aims: 1) to examine unique relations between parents' use of public assistance programs, including income support (i.e., TANF) and in-kind support (i.e., food stamps), and children's physical health, mental health, and cognitive development, 2) to examine whether these relations vary according to the timing and duration of program use, and 3) to investigate family-level mediators and moderators of relations between public assistance benefits and children's developmental outcomes. A variety of analytic techniques will be employed to address these goals, including propensity score analysis, latent curve modeling, finite mixture modeling, and structural equation modeling. Results of this research will expand existing information concerning how public assistance benefits received by low-income families relate to children's development, provide a nuanced examination of how timing and duration of benefit use alter these relationships, and illuminate developmental processes through which macro-level policies can affect children's development. PUBLIC HEALTH RELEVANCE: It is widely documented that low-income children are at greater risk for experiencing social-emotional, physical and academic difficulties than their middle class counterparts. This study examines relations between public assistance benefits available to low-income families and children's mental health, physical health, and cognitive development. This work will contribute to the growing body of knowledge that informs policies and practices designed to optimize developmental outcomes among low-income children.